This invention relates to cam guided systems and methods for plugging a pipe under pressure, and is particularly applicable for plugging a pipe, or pipeline having therein high temperature liquids or gases. “Pipe” as used hereinafter is inclusive of any tubular member made of metal for carrying fluid (liquids or gases).
The invention described herein is a cam-assisted, wedge actuated, double block and bleed, metal-to-metal high temperature valve.
Machines for tapping an opening in a pipe are well-known. Prior issued U.S. patents for tapping machines include U.S. Pat. No. 3,614,252 entitled TAPPING APPARATUS; U.S. Pat. No. 4,579,484 entitled UNDER WATER TAPPING MACHINE; U.S. Pat. No. 4,880,028 entitled COMPLETION MACHINES; U.S. Pat. No. 5,439,331 entitled HIGH PRESSURE TAPPING APPARATUS; U.S. Pat. No. 5,612,499 entitled METHOD OF INSERTING A SENSOR INTO A PIPELINE and U.S. Pat. No. 6,012,878 entitled PRESSURE BALANCED SUBSEA TAPPING MACHINE.
Tapping machines, such as the kind described in the above-mentioned U.S. patents, are for tapping a hole in a pipe while liquids or gases are flowing through them, that is, while the pipe is under pressure. Tapping procedures of this type are customarily carried out primarily for one of two purposes, that is, to provide a branch fitting on the pipe or to enable fluid flow through the pipe to be blocked. Other examples of prior art that describe and illustrate plugging the interior of a pipe usually associated with first tapping the pipe, include the following United States patents:
PATENT NO.INVENTORTITLEU.S. Pat. No. 3,170,226AllanLine Stopping and Valve InsertingApparatus and MethodU.S. Pat. No. 3,599,663Ver NooyHot Tapping ApparatusU.S. Pat. No. 3,626,475HicksHigh Temperature Pipe-PluggingApparatusU.S. Pat. No. 3,665,966Ver NooyPipe PluggerU.S. Pat. No. 3,785,041SmithMethod For Plugging PipeU.S. Pat. No. 3,872,880Ver Nooy et al.Plugging ApparatusU.S. Pat. No. 4,411,459Ver NooyBranch Fitting for Providing Access tothe Interior of a PipeU.S. Pat. No. 5,443,095Glossop, Jr.Fluid Blocking DeviceU.S. Pat. No. 5,531,250Freeman et al.Device for Plugging the Interior of aPipeGB1,064,398Pass and Co. Ltd.Pipe Line PluggerWO2004/099661TDW Delaware, Inc.Apparatus, Systems and Methods ForPlugging A High Temperature Pipe